Benefit-Cost Analyses of Introducing Electric and Natural Gas Buses in Hong Kong

Sustainability;Air Pollution;Hong Kong;Electric Buses;Natural Gas Buses;2020 Energy Mix;Value of Statistical Life (VSL);Roadside Pollution;Transportation;fuel use;monetized health impacts;emissions;renewable energy

Keller-Liang, Rosalind

University:Havard University

Department:Sustainability

关键词: Sustainability;    Air Pollution;    Hong Kong;    Electric Buses;    Natural Gas Buses;    2020 Energy Mix;    Value of Statistical Life (VSL);    Roadside Pollution;    Transportation;    fuel use;    monetized health impacts;    emissions;    renewable energy;   

Others  :  https://dash.harvard.edu/bitstream/handle/1/37365367/KELLER-LIANG-DOCUMENT-2018.pdf?sequence=1&isAllowed=y

美国|英语

来源: Digital Access to Scholarship at Harvard

【 摘 要 】

Air pollution can be detrimental to human health and the environment.In Hong Kong, cargo vessels and roadside transportation are significant contributors to poor air quality found in the city.There have been research studies and solutions proposed to curb emissions produced by cargo vessels. However, few studies have examined the effects of interventions on changing transportation options or technologies to reduce air pollution in the area. In this thesis, I investigated some potential ways to reduce emissions from road transportation.Emissions from diesel buses are one of the main contributors to roadside pollution in Hong Kong. Within a land area of 1,100 km², over 5,800 franchised, diesel buses serve the needs of commuters daily.Therefore, I have analyzed a few cases for new technologies to reduce air pollution emissions from this source.While Hong Kong produces a sizable share of its own emissions from coal-powered plants, road transport, vessels, and other means, the condition is complicated by inheritance of air pollution produced by factories operating in neighboring cities including Shenzhen and Guangdong.To mitigate pollution in the city, the Government of Hong Kong spent HKD180 million (USD23 million equivalent) to acquire thirty-six electric buses to be rolled out in phases that began in December of 2015.The pilot was a major environmental initiative and showed the Government was ready to engage in climate change mitigation measures.It is unlikely that electric buses might emit more pollutants from its power sources than conventional diesel buses, but we don’t know if the difference will be significant enough, given the city’s current energy mix has a high coal content.In theory, electric buses, or electric vehicles in general, can produce a substantial effect on carbon reduction if the power source or energy mix has a high composition of renewable energy.Otherwise, the emissions are simply transferred from street level to the coal-powered plants – city level.In view of this theory, this thesis aims to quantify the health and environmental impacts of potential solutions for cleaner road transport options in Hong Kong.My main hypothesis is that there might be positive impacts on public health should the entire fleet of public franchised buses be replaced by electric buses in Hong Kong.A secondary hypothesis is that--resulting from reduction in lung diseases, breathing disorders and cardiovascular disease—overall rates of mortality and morbidity would be reduced between 20 and 30%.To test these hypotheses, I used a methodology that integrates air pollution information in Hong Kong with environmental exposure techniques to assess changes in air pollution concentration for fine particulate matter that can translate to increases or decreases in overall cardiovascular mortality by using epidemiology studies.These health impacts are estimated for three public transportation scenarios – regular use of franchised diesel buses, regular use of franchised natural gas buses, and total substitution of conventional diesel buses with electric buses.Background data for cardiopulmonary and lung cancer mortality in 2016 were obtained from the Health Ministry in Hong Kong. Health impacts for each scenario were monetized and the costs for each scenario were classified as capital, operation, and health impact costs.Monetized public health impacts for each scenario were estimated by determining differences in the cardiopulmonary and lung cancer mortality resulting from different transportation scenarios.Cost efficiency for each scenario is estimated by obtaining their Benefit-Cost Ratios which are the division of the overall monetized public health impacts of each scenario by the cost of this intervention.Mortality prevented or increased was transformed into money by using the Value for Statistical Life (VSL) saved which is derived from how much people are willing to pay to prevent a negative health outcome. Other factors including fleet age composition, bus usage to define fuel use, vehicle kilometers travelled and maintenance records were considered when estimating benefit cost ratios for each scenario. These ratios might serve as objective information to draft policy recommendations to improve the sustainability of public transportation in Hong Kong.